Internal-combustion engine



C. M. LEECH, DEC D. c. E. KINDELL, ADMINISTRATOR. .INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 1. 1920.

Patented Feb. 21, 1922.

4 SHEETS-SHEET 2- C. M. LE DECD. C. E- KINDELLI D INISTRATOR.. INTERNAL comsusnom ENGINE.

APPLIC AT|ON FILED APR. 1 192a. Patented Feb 219 1922',

4 SHEETS-SHEET 3.

C. M. LEECH, DECD. C- E- KINDELL, ADMINISTRATOR- INTERNAL COMBUSTION ENGINE.

APPLICATION FILED APR. 1 1920. 1,407, Patented Feb-21, 1922.

4 SHEETS-SHEETM m 4 u WJ w 1 f 5 i .l /I F W n m F m, 32/ 0 l o 0 Z J o a o a y u 0 0 a W CHARLES M. LEECLEH, 0F CLEVELAND, OHIO;

SAID CHARLES M.

CHARLES E. KIN DELL ADMINISTRATOR 031 LEECH, DECEASED.

INTERNAL-COMBUSTION ENGINE.

Z 0 all whom it may concern.

Beit known thatI, CHARLES M. LEEOH, a citizen of the UnitedStates, residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Internal-Combustion Engines, of which thefollowing is a full, clear, and exact description.

This invention relates to internal COIII- bustion engines offthe two-cycle type, and

has particular reference to engines constructed along the lines of, and embodying certain features of engines disclosed in several prior patents granted to me, including Patents No. 1,138,876, May 11, 1915; No. 1,068,595, July 25, 1913; No. 914;,292, March 2; 1909; No. 1,082,494, May 9, 1916 and No. 1,099,065, June 2, 1914.

The principal'object of the invention is to provide certain improvements which render a two-cycle engine, particularly of the single cylinder type, more eflicient and satisfactory in operation, the invention in certain respects having particular reference to a single cylinder engine, though other features are'adaptable for engines having more than one cylinder.

The invention pertains particularly to certain improvements in the construction of the jacket by which the engine cylinder or cylinders are cooled by air; also to the manner of forming the cylinder, particularly the lower pumping portion by which mixture is more or less compressed and driven into the working portion of the cylinder, the last mentioned feature having special utility for a single cylinder twocycle'flengine, and it pertains also to the manner of forming the piston. Additionally the inventionrnay be said to consist .in certain "novel details of construction and combinations and arrangements/of parts which will be described in the specification and set forth in the appended claims. 3

In the accompanying sheets of drawings, wherein I have shown the preferred embodiment ofa single cylinder, two-cycle engine constructed in accordance with the present invention, Fig.1 is avertical sectional view of an engine equipped with'a preferred form of my invention; Fig.2 is another vertical sectional View taken at substantially right an les to the section of Fig. 1; Fig. 3 is a sic e elevation of the engine; Fig iis a top plan view,- and Fig. 5 "is a horizontal sec Specification of Iietters Patent.

ends of the body 'necting rod to the piston.

Patented Feb. 21, 1922. 1920. Serial No. 370,508.

tional view substantially along the line 5-5 of Fig. 1. Y i

In the drawings, 10 represents a crankcase and 11 the main cylinder casting in the 'uppenworking portion of which is'adaptcd to reclprocate a piston 12 connected by a connecting rod 18 to a crank-shaft 1 1. It

-will be observed that the crank-case is c0Inposed of a cylindrical body portion 10 with two circular. end plates 10 bolted to the portion and having bearings 10 for the crankshaft 14. At the top of the body portion of the crankcase there is an integral tubular extension 15, whose axis is coincident with the axis of the piston, and which forms the'inner wall of a pumping cylinder aswill be explained presently. It will be observed that the connecting rod extends downward through this tubular extension 15 to the crank-shaft.

The, cylinder casting 11 has an upper working portion 11 in which the upper part of the piston slides, and it has an enlarged lower portion 11 which is concentric with respect to the tubular extension 15 of the crankcase and forms the outer wall of the pumping cylinder. It will be observed that the tubular extension 15 of the crank-case is somewhat smaller in external diameter than the internal diameter of the working portion 11 of the cylinder casting, and that this tubular extension 15 terminates just below the shoulder formed at the junction of the working and pumping portions of the cylinder casting.

The piston 12 is composed of a head 12 anda sleeve-like extension 12 these parts being separately formed, and being fastened together by screwing the head into the upper part of the sleeve 12". The head 12 has a boss 12 to which the upper end of the connecting rod 13 is pinned,this boss being located b'elowthe annular threaded part of the head which is screwed into the sleeve part 12 of the piston so that it is possible to readily machine theboss to accommodate the pin which fastens the con- It will be observed that when the piston is at the bottom of its stroke the boss 12 extends down into the tubular extension 15 of the crank-case sothat the ordinary method of connecting a piston and connecting rod can not be utilized with this construction, it being therefore important a production .encebetween the inner diameter of the work ing port-ion of the cylinder and theexternal diameter of the tubular extension 15 of the crank-case being equal substantially to the thickness of the sleeve 12 of the piston.

The upper part of the sleeve 12 of the piston has anumber of piston rings 16 engaging the working portlon 11 of'the cylinder,

the upper ring 16 being held in place by a peripheral flange of the head which extends over the extreme upper end of that portion of thesleeve '12" to which the piston head I is attached.

Additionally the upper part of th crank-case extension 15 has a piston ring 17 which engages the inner wall of the piston sleeve 12". The lower part of the piston sleeve12 has a lateral extension coir stituting a secondary piston 12, this lateral extension or pumping piston having a piston ring 12 engaging the pumping portion 11 of the cylinder casting. As will subsequently appear, the lower part of the piston sleeve, i. e., the pumping portion, forms a double acting piston for thetwo-fold purpose of circulating or pumping air for cooling the upper part of the cylinder, and for the purpose of pumping mixture into the working portion of the cylinder.

Mixture is supplied to the engine independently of the crank-case, except the tubular extension '15 which serves as apart of the pumping cylinder for the mixture, through a rotary valve 18 which is preferably driven by the crank-shaft at one-half the speed of the latter, this valve being mounted to rotate in a ported sleeve -19 in a valve casing'20 formed at the lower part of the cylinder casting 11. This valve will have a suitable connection with the carbureter, and it has a pair of oppositely disposed ports 18, one of which at each revolution of the crank-shaft and 011 the up stroke of the pistonadmits mixture through a port 21 into the space beneath the pumping portion l2 of the piston between the pumping'portion 11 of the cylinder and the tub -ul'ar. extension of the crankcase.

.up stroke of thepiston the pumping por- .tiOnlQ sucks a charge into the space just On the referred to, and on the down stroke the mlxture :is expelled from this chamber or cylinders-through a port 22, in this case diametrically opposite from the inletport .21, and from this port the mixture is driven through an upwardly extending passageway 23, at the top of which is a rotary "throttle valve 24 which controls ahead- :Il'llSSlOIl of the mixture into the cylinder,

this throttle valve in this instance co-operating with a series ofvertically disposed inlet ports 25 "leading from the chamber of the throttle valve tofthe working portion of thecylinder as shown in several of my prior patentsalready referred to. These ports are uncovered by the piston at or about the bottom of the piston stroke, and

at or about the same time the piston unthat a certain amount of heat will be trans.

mitted to the mixture before passing into the engine, and the exhaust is carried from the cylinder casting by an exhaust pipe 28.

screwed into the casting just above the inlet It may be stated at this point that when the piston approaches theend of its upward stroke, air maybe admitted through a port.

29 which port is controlled by an auxiliary valve 18. 1 Y

valve 30, likewise of the rotary type, which in this instance is connected by a rod 31 to the throttle valve 24 so as to work in unison therewith. In other words, when the engine is :throttled down,- this port will be practically or-entirely closed, but when .the throttle valve is opened to speed up the engine, this auxiliary air port is opened so .as to allow more air to be admitted to the mixture.

While the auxiliary air valve 30 is preferably connected to-the throttle valve so as to work in unison therewith, nevertheless I contemplate having this valve operable by hand or otherwise independently-ofthe throttle valve. This valve .30 is preferably in the form of a sleeve for hollow tube which for a single cylinder engine is open at one or both endsbut for an engine of four or six'cylinders the tube is preferably open between the cylinders as well as at its ends so asto give itample'capacity andproride for equal distribution of air to all the cylinders. It will into the pumpingportion of the cylinder, and on the down stroke this mixture; is driven into the chamber or passageway 23, the inlet valve 18 being so timed that communication between the lower pumping portion of the cylinder and the inlet valve 18 is closed before the piston starts on its downward stroke. During the major portion of the downward stroke of the piston, the mixture is compressed in the lower pumping portion of the cylinder and in the chamber or passageway. 23, and as soon as thepiston uncovers the inletqoorts 25, the mixture rushesinto the working' portion of the cylinbe understood, therefore, that on i the up stroke ofthe piston a charge is sucked der, expelling the burnt gases resulting from the combustion of the previous charge in the cylinder.

Having explained the pumping function of the pumping portion of the piston so far as it relates to the supply or" mixture to the working portion of the cylinder, I will next explain the pumping function of this portion of the piston in so far as it relates to the cooling of the cylinder. It will be observed that the working portion of the cylinder is surrounded by a jacket 29 which is secured by'a nut 30 to a tubular extension on the cylinder head at the top of the cylinder, this jacket 29 surrounding external vertical fins 31 on the upper working portion of the cylinder and extending downward to a point just below the shoulder formed by the junction of the working and pumping portions 11 and 11" of the cylinder casting. This shoulder or lateral extension of the cylinder castin is provided with a series of air ports to 32 located between the fins 31, these ports 32 communicating with the vertical spaces be- 1 air is sucked into the air tween the fins enclosed by the jacket, and communicating with the pumping cylinder or chamber formed above the pumpingportion 12 of the cylinder and the sleeve 12 of the piston. Additionally the jacket 29 is provided just above the openings 32in the cylinder castingwith lateral ports or openings 33 which may be termed air intake openings, and at the top the jacket is provided with openings 34 which may be termed air exhaust openings. The construction is such that on the down stroke of the piston pump cylinder, this being the stroke which drives the gas beneath the pumping portion of the piston from the gas pump cylinder into the compression chamber 23, and finally into the working portion of the cylinder. On this down stroke of the piston cool air is sucked into the lateral ports or openings 38, and some air is, of course, at the same time sucked into the upper openings 84. On the up stroke air is expelled by thepumping portion of the piston through the air pump cylinder, out through the openings 32, and up along the wall of the working portion of the cylinder, and out through the upper openings 3% so that a maximum cooling actionis obtained.

The engine above described is not only extremely eiiicient in operation, but the con struction is simple, rendering itpossible to produce the engine in quantities at low cost.

I do not desire to be confined to the exact details shown, as changes may be made with out departing from the spirit and scope of my invention in its broadest aspect.

Having described my invention, I claim 1. In an internal combustion engine of the two cycle type, a crank case having a cylindrical extension, a cylinder having a working portion and a pumping portion, the pumping portion surrounding the crank case extensioma piston engaging the working portion of the cylinder and having a sleeve surrounding the extension of the crank case and having a pumping portion adapted to reciprocate between the pumping portion of the cylinder and the crank case extension, ports in the pumping portion of the cylinder for the admission of mixture to the space beneath the pumping portion of the piston and for the delivery of the mixture to the working portion of the cylinder, and an air port in the pumping portion of the cylinder adapted to be uncovered by the pumping portion of the piston on the suction stroke thereof.

2. In an internal combustion engine of the two cycle type, a crank case having a cy1indrical extension, a cylinder having a working portion and a pumping portion, the pumping portion surrounding the crank ease extension, :1 piston engaging the working portion of the cylinder and having a sleeve surrounding the extension ofthe crank case and having a pumping portion adapted to reciprocate between the pumping portion of the cylinder and the crank case extension, ports in the pumping portion of the cylinder for the admission of mixture to the space beneath the pumping portion of the piston and for the delivery of the mixture to the working portion of the cylinder, and a valve controlled air port in the pumping portion of the cylinder adapted to be uncovered by the pumping portion of the piston upon the suction stroke thereof.

3. In an internal combustion engine of the two cycle type, a crank case having a cylindrical extension, a cylinder having a working portion and a pumping portion, the pumping portion surrounding the crank case extension, a piston engaging the working portion of the cylinder and having a sleeve surrounding the extension of the crank case and having a pumping portion adapted to reciprocate between the pumping portion of the cylinder and the crank case extension, ports in the pumping .portion of the cylinder for the admission of mixture to the space beneath the pumping portion of the piston and for the delivery of the mixture to the working portion of the cylinder, and a throttle valve, an air valve coupled thereto and a port controlled by said air valve for supplying air to the mixture on the pumping stroke of the pumping portion of the piston.

In testimony whereof, I hereunto aiiix my signature.

CHARLES M. LEECH. 

